We usually think of the RTL-SDR as a low-cost alternative to a “real” radio, but this incredible project spearheaded by [Rodrigo Freire] shows that the two classes of devices don’t have to be mutually ...

Listening to police and fire calls used to be a pretty simple proposition: buy a scanner, punch in some frequencies — or if you’re old enough, buy the right crystals — and you’re off to the races. It ...